Woman reports that two friends, a man and his wife, were in their boat fishing off of Diamond Head, Oahu Island. At approximately 0500 hrs., both of them heard a very loud noise, "like two large trucks," and observed a bizarre hump-backed, triangular object hovering in the sky nearby. The object had "windows," but they were opaque. The object was seen to move, but only very slowly. When it moved, the red light on the ventral side of the object alternated red and green blinking. Then it moved toward the vicinity of Diamond Head, where it hovered for 5 minutes, after which it moved slowly westward along the coastline and finally disappeared from sight.